The present invention relates to a wind turbine having a generator with stator and rotor in a machine housing that is disposed at the top of the wind turbine tower, wherein the stator has a support construction comprising a plurality of support arms. The generator of the wind turbine is a ring generator.
Wind turbines are known and are already used in large numbers. The development of wind turbines is tending towards greater generator output. This trend is often accompanied by an increase in the dimensions of the separate components (especially their support arms) and hence their mass.
Today""s prior art, as shown in FIG. 1, has a wind turbine 1 whose nacelle 2 weight (machine housing weight) is in the order of 90-100 tons. Part of this weight is that of the stator support 12 to which the stator 20 of the generator is mounted. Such prior art includes blades 3 coupled to a rotor 4. The rotor 4 has connected thereto an electrical rotor system 5 for generating electricity in interaction with the stator 20 in a manner well known in the art. The wind turbine is thus composed of a relatively large mass. However, such large masses are difficult to handle and generate considerable stress on both the tower and the tower foundations, leading not only to increased material stress, but also to greater costs for the separate, aforementioned components of a wind turbine. Reference is made by way of illustration to the fact that the nacelles (that is, the machine housing) of the wind turbine are not only transported to the building site, but in many cases must be hoisted in their separate parts to the top of the tower.
Another problem encountered with wind turbines relating above all, in addition to building law issues, to the acceptance of such turbines among the respective neighborhood, is that of noise emission, in that the noise emissions produced even by modern wind turbines constitute a disturbance and can therefore reduce the acceptance of such turbines.
Part of the noise emissions are generated by the support arms, since these have a hollow interior and sealed outer surfaces, with the result that a resonant body is formed.
One object of the present invention is therefore to specify a wind turbine whose components have reduced weight and whose noise emissions are lowered.
This object is achieved in accordance with the invention by the stator support having an open structure. This open structure results in reduced weight, on the one hand, as well as less material being used, on the other. Noise emissions are also reduced, because by virtue of their open structure the support arms can no longer form a resonant body, thus eliminating the noise emission of the support arms, at least.
Due to its lower weight compared to previous designs, a stator support according to the invention thus helps to reduce the mass of the nacelle, and hence to improve handling and transportability of the components and/or the entire nacelle.
Other preferred embodiments are characterized by the subclaims.